Combined telephone and alarm system.



PATENTEDJULY' 10, 1906.

H. G. WEBSTER. COMBINED TELEPHONE AND ALARM SYSTEM.

APPLICATION FILED-JULY 11, 1904.

2 sums-sum 1.

WW %/A Q PATENTED JULY 10, 1906.

H. G. WEBSTER. COMBINED TELEPHONE AND ALARM SYSTEM.

APPLICATION FILED JULY 11, 1904.

2 SHEETS-SHEET 2.

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UNITED STATES rngrnntr oFFIoE.

HARRY Gr. WEBSTER, OF CHICAGO, ILLINOIS, ASSIGNOR TO MILO (3-. KELLOGur, OF CHICAGO, ILLINOIS.

COMBINED TELEPHONE AND ALARM SYSTEM- Specification of Letters Patent.

- ratented July 10, 1906.

Application filed July 11,1904. Serial No- 216,083.

, Chicago, county of Cook, and State of Illi nois, have invented certain new and useful Improvements in a Combined Telephone and .Alarm System, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming art of this specification.

.My invention re ates to systems in which line-circuits extending from a telephone-exchange to subscribers stations are utilized for the transmission of special fire, burglar, and other alarm signals in addition to then ordinar telephomc use.

he object of my invention is to provide anim rovement upon a systemproposed hereto ore, in which the line-circuit is at all times available for the transmission of an alarm: signal and in which the alarm sending and alarm-receiving apparatus do not cause any interference with telephonic signaling or conversation except upon the sending of an alarm-signal, when the telephonic requirement may be disregarded. n such a system it is desirable that an alarmsignal should be permanently maintained at the receiving-station until acted'upon by the person in charge, that the indication given should be one which is positively the result of the actuation of the'alarm-sending ap aratus, that its nature should be such tiat the alarm-receiving operator may determine instantly from which particular line the signal is being sent, and that the apparatus em loyed should be of the most simple and relia le. character.

The improvement of my present invention consists in novel means for meetin these requirements. It has been proposed to employ as an alarm-sending device in such a system mechanism in the nature of "the ordinary district-messenger box, which shall intermittently break or make a circuit of the line to produce a 'dot-and-dash or code" signal at the receiving-station. Under such an arrangement it is necessary that there should be a separate register or recordin device for each line or that the makes an breaks should be of a different character for each sending-station of the "system.

In accordance with my present invention I am enabled to employ sending devices which are uniform and interchangeable, as Well as to avoid the use of a bulky and cumbersome receivin device, such as a telegraph-register. f n a preferred embodiment employ sendin mechanism which will produce makes or breaksof regular, definite, and relatively slow frequency, and preferably of definite number, and receiving mechanism which will only give an indication after receivin a certain number of pulsations of the determined frequency. Sending devices'of this character are well known, such as a revolving contact-wheel controlled. by an esca ement or fan governor and adapted to e released manually or automatically, and I do not limit myself to any specific mechanical construction or arrangement in such a device. i

The receiving device consists of an electromagnet associated with the line either directly or indirectly in a manner to be energized and denergized by the pulsations set up by the sending mechanism and make this electromagnet act upon a vibrating armature, which, through being weighted or otherwise, will synchronize with such pulsations and after a sufiicient number have been sent will produce an audible signal (as upon a bell) or will close the local circuit of an electrical signal This electrical signal consists; preferably, of a mechanical tar et or an incandescent lam so arranged tdiat after its circuit is once 0 osed it will remain displayed until efi aced by the alarm-receivin operator.

In a modified construction the a eve-mentioned electromagnet acts upon a slow-acting armature carrying a pawl which engages a ratchet-wheel. This ratchet-wheel has associated with it a commutator and brushes and is revolved one tooth at each attraction or retraction of the armature. If the wheel comes to rest after the determined number of pulsations, contact is made between a brush and a commutator-segment, which completes'a local circuit including the signal; but if the number of pulsations is greater or less than the determined number' a signal as-'.

sociated with a difierent commutator-segment indicates that the wheel is to be restored to its normal position by the operator.

too

I have illustrated my invention in the accompanying drawings; in Which Figure 1 is a diagram showing two subscribers lines and the centralrstation connecting apparatus of the well-known twowiretelephone system as embodymgh my invention inapreferred form. Fig. 1* ows the alarm-receiving apparatus with a mechanical-target signal. Fig. 2 1s a diagram. illustrating a modification of the system of Fig. 1 in an exchange system of the threehe bell and condenser a being in permanent bridge of the line. The limbs 1 and 2 ofthe line extend to the central office and are there connected, limb 1 to the contacts of the cutoff relay 3, the line-relay 4, andto the live side of the battery C, and'limb 2 of those lines which a e not equipped for alarm service is carried: irect to the grounded side of the battery through contacts 5- and 6.01 the relay 3. A subscriber in calling raises his receiver and com letes the low-resistance circuit through 1118 transmitter and hook-switch contact to actuate the relay 4, lighting his linelamp 7. Upon the insertion ofan answering-plugP the operation of relay 3- cuts off the ground and the relay 4, extinguishin the linelamp, and connecting the line-lims to the jacks 17 and 17 and thenceto the strands 14 and 15 of the-cord. Current is now su plied to the line from battery G through re eye 9 and- 10, which also control the supervisory lamp 8, they lamp remaining dark as long as current flowsthrough relay 10. The oper-' ator tests, plugs in, and rings a wanted subscriber in the usual way with calling-plug O andf-ringing-key g. g. While ringing, the relay 3 is energized by current from battery E and generator'G, and after the ringing-key is released: relay 12 and relay 3 are energized by current from battery D. The relay 12 when thus actuated cuts off the test-relay 19 and completes the circuit ofstrand 14 at its contactsi and also. com letes the circuit of supervisory lamp 11. en the called subscriber answers, currentis furnished his instrument through relays 12 and 1-3, and, the energizetion ofrelay 13 eff-aces lamp 11, which remains dark until the receiver is replaced.

The subscribers are now able to converse over strands 14 and 15, which include the con densers (Z, (Z of the cord-circuit. The hanging up of both receivers deprives the relays 10 and 13 of current, thus completing the circuits of lamps 8 and 11, which being illumi nated constitute the disconnect-signal. This is the regular telephonic o eration of the system and is not interfere with by the resence of the alarm a paratus upon suchhnes as are provided wit it. Such lines are. provided withthe high resistance and impedance I in bridge of the line. The electromagnet F is connected from limb 2 to ground or to the office return, and the batterYconnection 0% contact 6 is remeved' or; carried.

through a resistance 16 to equalize the cur rent of magnet F. The resistance of is so proportioned that it will: allow a normat current toflow sufiicient. toenergize the magnet of relay'F, but not sufficient in volume .to cause the armatures (iii-relays is, 1:0 or 113i to be attracted or held; u

The make-arid-breas device is illustrated at M, the circuit of limb- 1 bein normally closed through Wheel n and brus" o. This wheelis prevented: trorn revolving as long-as the relerising-lever S is attracted by the mag net m to engage the fian-govemer-v, the. magnet mbeing energized by current from bat tery 18 over a circuit including the thermostats 01: other circuitbreakin devices When the mechanism is nel'eas the circuit of limb 1 and battery C is broken each time an insulated portion of wheel n passes-under brush 0-, and the rate of intercu tion is. com paratively slow as compared with the alternations of the ringing-generator G. A stop 31- is provided blywhich thewheel; is brought to rest after ma ing the required; number: of interruptions The magnet F' ;is provided with a swinging orrocking armature, so balanced or weighted that it will only vibrate at a certainratenameLy, that of the interruptions produced in the line by the device and that a certain number'ofi pulsations ofcurrent through the magnet F will be re quired before it can attain its full amplitude ofi vibration. When this point is reached, the armature completes acircuit ofibattery 2-2-through contact 21,.resistance24, and re-- la, 23. The relay being thus energized,

closes byi-ts contact 25 a circuit through shown in its normal condition, while at line B the circuit of battery 18' and magnet m having been broken at f the i errupting mechanism has been opera-ted an the signal transmitted: It is to be noted that the-current which energizes magnet F normally flows from battery Othrough relay 4, limb-1, im-

pedance I, and limb 2-to ground or office return; but during the presence of-a connectingplug in a jack t e path of current is from battery Othrough relay 9, limb 1, impedance I, and limb 2, where it divides, a portion returning through magnet F, and the remainder through relay 10 and under either condition the removal of the subscribers receiver sim- 'ply increases the volume of current to the point necessary to operate the relays controlling the telephone-sig'nals. It will also be seen that the display of the.alarm-signal will not be produced by the rapid alternations of the calling-generator, nor by irregular or intermittent interruptions due to inter ference with the line-wires themselves.

switch being provided to cut out the bellwhen desired.

Fig. 2 is a conventional diagram illustrating my invention in an exchange of the wellknown three-wire type. Telephonically, this system differs from that of Fig. 1, in that the cut-off relay is included in a third wire, and the jack-terminals are permanently connected to the line. .As in the system of Fig. 1, current is normally flowing in the line through line-relay 4 and impedance 1. Upon the insertion of a connecting-plug the relay and battery return'are removed by the action of the cut-off relay, and current is then supplied to the line through the coi'd strancls and Lack-terminals in the manner well understood y those skilled in the art. The interrupting mechanism of Fig. 1 is indicated diagrammatically at M but the receiving apparatus instead of being connected directly between limb 2 and the ground is indirectly associated with the line by means of the serially-included relay H. ,This relay being directly in the talking-circuit has its win ings arranged so as to present little or'no impedance to voicecurrents, and the resistance preserves the balance of the line. At each interruption of the circuit at.M the relay contact-piece 36 falls back, engaging contact 37, thus energizing the magnet F by means of its winding 32. The armature a is thus set in vibration and on reaching its full range enga es contact 34, completing the circuit of. attery 22 through winding 33 and lamp 26, and is thus held attracted in this osition. The lamp remains lighted until t e circuit is opened again at key 27, when the lamp and armature return to normal. The relay H is always ener ized by currentfi om battery C'or from the caling-generater'aslong'as the circuit is insulated portion 43.

complete throu h the line-limbs, and while it may be release through accidental opening or grounding of the line-circuit the signallamp 26 will not light until the armature a has received the proper number of impulses at the proper frequency from the magnet F.

Fig. 3 illustrates an alternative receiving device in which an accidental grounding or opening of the circuit will give a special signal, but in which the alarm-signal will not be displayed until the proper number of impulses has passed. In this case relay H is included in limb 2 of the line, as in Fig. 2, and controls the circuit of magnet J. The armature 38 of this magnet carries a pawl 40, which engages the teeth of the ratchet-wheel 42, controlled by the detent 41. This wheel carries with it a contact-wheel 44, having an Brush 47 is always in contact with the main: portion of this wheel and brush 46 with the insulated portion, While brush will make contact with either ortion as the Wheel revolves. When the ine-circuit is interrupted, as in case of an alarm, the relay H is deenergized and the circuit of magnet J opened, and providing the breaks and makes are of the proper frequency the ratchet-wheel is carried forward one tooth at each closure of the line-circuit. After the requisite number of interruptions as determined by the stop 31, the wheel 42 comes to res't'at a point where circuit is completed from battery 22 through brush 45, portion 43, brush 46, and lamp 26, which being illuminated indicates an alarm. If, however, through outside interference with the circuit the current through relay H is interrupted a number of times greater or less than that required circuit will be closed through brush 45, portion 44, brush 47, and lamp 48, and the consequent illumination of this amp constitutes a signal to the alarm operator of such interference and that the mechanism is to be restored to its normal position.

Figs. 4 and 5 illustrate arrangements of wiring, whereby the alarm-receiying apparatus may be systematically associated with or changed to any exchange-line,' Fig. 4 1llustrating the case where the relay F is serially included in the line, and Fig. 5 that Where the connection is from limb 2v to the ground .or oflice return. It will of course be evident that magnet F of Fig. 1 could be substituted for the relay H of Fig. 5. As will be readlly understood, those circuits which are not provided with the alarm equipment enter the exchan e by their limbs 1 and 2 at terminals 49 of t e main distributing-rack K and are carried by flexible jumper-wires (not shown) to terminals 50 and thence to the telephoneswitchboard by permanent wires. The alarm &

jumpers from .49 and 50 and re-- place them by special jumpers, as indicated y li nes 52, 53, 54,. and 55. The usuallightmug and sneak current protectors are indi-- eated at 56.

, It will be understood that the several grounds indicated are or may be the exchange return and also that the several batteries 0,

I), E, and 22 may be one and the same.

While I have particularly described my in ventionwith regard to certain details ofconstruction and arrangement, it is evident that many modifications may be made therein by those skilled in the art Without departing substation toa. telephone-exchange, means for supplying a relatively small current to said circuit, telephone signaling means for sending. an increased current over said' cuit, telephone signal-receiving means operated only in response tosuch increased current, alarm signal' transmitti means for sending decreased current pulsatlons of regular fi'equency over said circuit, alarm-receiving means operated only in response to said decreased current pulsations, and means at the substation and exchange for holding con- 'versation over said circuit.

2. A combined telephone and alarm'system comprising a circuit extending from a substation to a telephone-exchange, means for supplying a relatively small current to said 0H011it,; telephone signaling means for sending an increased current over said circuit, telephone signal-receiving means operated only in response to such increased current, alarm-si nal-transmitting means for interrupting sai circuit at a regular frequency, alarrmreceiving means operated only in response to said interru trons, and means at t e substation and exc ange for holding conversation over said circuit. v.

3. In a tele hone-exchange system, the

- combination 0 a subscribers line, alarmsending apparatus for the line, adapted to set up electrlc pulsations therein. of regular frequency and number, and alarm-receiving apparatus adapted to respond only after a definite number of pulsations ofsuchfrequency,

substantially as described.

-4. In a telephone-exchan e system, the combination of a subscribers ine, a source of current at the exchange, alarm-sending apparatus adapted to set up electric pulsations of regular number and frequency of said source in the line, and alarm-receivin apparatus associated with the line adapts to respond only after a definite number of such pulsations, substantially as described.

5. In a telephone-exchange system, the combination of a subscribers line, alarm-receiving apparatus associated with the line adapted to give an indication in response to a definite number of current variations in the line of a predeternn'ned frequency, and alarmsending apparatus associated with the line adapted to produce such current variations therein, substantially as described.

6. In a telephone-exchan e system, the combination of a subscribers he and instrument, alarm-sending apparatus exterior to the exchange ada ted to set up regular electric pulsations in t e line, alarm-receiving apparatus associated with the line adapted to respond after a definite number of such pul-' sations only, and means for maintaining the alarm-signals constant until effaced by the operator, substantially as described.

7. In a tele hone-exchange system, the combination 0 a subscribers line, alarmsending apparatus associated with the line and adaptedto set up electric pulsations in the line regular in number and frequency, an electromagnet associated With the line, and mechanism controlled by said ma net adapted to cause the display of an a arm-signal only after the transmission of a definite number of said pulsations, substantially as described;

8. A combined telephone and alarm system comprising a circuit extending from the substation to a telephone-exchange, means for supplying a relatively small current to said circuit, telephone signaling'means for sending an increased current over said circuit, telephone signal-receiving means operated only in response to such increased current, alarm-signal-transmitting means for sending decreased current pulsations of regular frequency over said circuit, alarm-indicating means included in a local circuit, a relay included in said first-mentioned circuit and responsive only to the decreased current pulsations therein to close said local circuit to cause the actuation of said alarm-indicating means, and means at the substation and'exchange for holding conversation over said first-mentioned circuit.

9. A combined telephone and alarm system comprising a circuit extending from a substation to a telephone-exchange, means for supplying a relatively small current to said circuit, telephone signaling means for sending an increased current over said circuit, telephone signal-receiving means opera ated only in response to such mcreas'ed current, alarm-signal-transmitting means for sending decreased current pulsations of regular frequency over said circuit, alarm-indicating means includedin a local circuit, a relay included in said first-mentioned circuit and responsive only to the decreased current pul- ,sations therein to close saidlocal circuit to cause the actuation of said alarm-indicatingmeans, means whereby the display of said alarinndicating means is maintained independent'of said relay until effaoed by the operator, and means at the substation and'eX-gover said the line, regular in number and frequency, an.

electromagnet associated with the line, mechanism controlled by said magnet adapted to cause the display of an alarm-indicator in response to a definitenumber of said pulsations and to display a separate signal in response to pulsations diiiering in number'fi'om said definite number, substantially as 'de scribed.

11. A combined telephone and alarm system comprising a circuit extending from a substation to a telephone-exchange, means for supplying a relatively small current to said I sending an increased current over said cirated only in response to such rent, alarm-signal-transmitting means for of said circuit, telephone signaling means for sending decreased current pulsations of regular frequency over said circuit, mechanism operated only in response to said decreased current pulsations to display an alarm-signal in response to a definite number of said pulsations andto display a separate signal in response to. pulsations diifermg in numberfrom said definite number.

12. A combined telephone and alarm system comprising a circuit extending from a substation to a telephone-exchange, means for supplying a relatively small current to said circuit, telephone signaling means for sending an increased current over said circuit, telephone signal-receiving means operated only in response to such increased ourrent, alarm-signal-transmitting means for interrupting said circuit at a regular frequency, mechanism operated only in response to said interruptions to cause the displayof an alarm-signal in response to a definite number pulsations and to display a separate signal in response to pulsations difiering in number from said definite number.

In witness whereof I hereuntciysubscribe my'name this 30th day of- June, A D.

HARRY G; WEBSTER;

Witnesses:

'JULIA M. BRISTOL, F.'W. DUNBAR. 

